linux/include/net/netfilter, branch v6.3

netfilter: nf_tables: validate catch-all set elements

2023-04-18T07:12:22Z

catch-all set element might jump/goto to chain that uses expressions that require validation. Fixes: aaa31047a6d2 ("netfilter: nftables: add catch-all set element support") Signed-off-by: Pablo Neira Ayuso

netfilter: tproxy: fix deadlock due to missing BH disable

2023-03-06T11:09:48Z

The xtables packet traverser performs an unconditional local_bh_disable(), but the nf_tables evaluation loop does not. Functions that are called from either xtables or nftables must assume that they can be called in process context. inet_twsk_deschedule_put() assumes that no softirq interrupt can occur. If tproxy is used from nf_tables its possible that we'll deadlock trying to aquire a lock already held in process context. Add a small helper that takes care of this and use it. Link: https://lore.kernel.org/netfilter-devel/401bd6ed-314a-a196-1cdc-e13c720cc8f2@balasys.hu/ Fixes: 4ed8eb6570a4 ("netfilter: nf_tables: Add native tproxy support") Reported-and-tested-by: Major Dávid Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf-next

2023-02-20T10:53:56Z

Pablo Neira Ayuso says: ==================== Netfilter/IPVS updates for net-next The following patchset contains Netfilter updates for net-next: 1) Add safeguard to check for NULL tupe in objects updates via NFT_MSG_NEWOBJ, this should not ever happen. From Alok Tiwari. 2) Incorrect pointer check in the new destroy rule command, from Yang Yingliang. 3) Incorrect status bitcheck in nf_conntrack_udp_packet(), from Florian Westphal. 4) Simplify seq_print_acct(), from Ilia Gavrilov. 5) Use 2-arg optimal variant of kfree_rcu() in IPVS, from Julian Anastasov. 6) TCP connection enters CLOSE state in conntrack for locally originated TCP reset packet from the reject target, from Florian Westphal. The fixes #2 and #3 in this series address issues from the previous pull nf-next request in this net-next cycle. ==================== Signed-off-by: David S. Miller

netfilter: let reset rules clean out conntrack entries

2023-02-17T12:04:56Z

iptables/nftables support responding to tcp packets with tcp resets. The generated tcp reset packet passes through both output and postrouting netfilter hooks, but conntrack will never see them because the generated skb has its ->nfct pointer copied over from the packet that triggered the reset rule. If the reset rule is used for established connections, this may result in the conntrack entry to be around for a very long time (default timeout is 5 days). One way to avoid this would be to not copy the nf_conn pointer so that the rest packet passes through conntrack too. Problem is that output rules might not have the same conntrack zone setup as the prerouting ones, so its possible that the reset skb won't find the correct entry. Generating a template entry for the skb seems error prone as well. Add an explicit "closing" function that switches a confirmed conntrack entry to closed state and wire this up for tcp. If the entry isn't confirmed, no action is needed because the conntrack entry will never be committed to the table. Reported-by: Russel King Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso

net: extract nf_ct_handle_fragments to nf_conntrack_ovs

2023-02-11T00:23:03Z

Now handle_fragments() in OVS and TC have the similar code, and this patch removes the duplicate code by moving the function to nf_conntrack_ovs. Note that skb_clear_hash(skb) or skb->ignore_df = 1 should be done only when defrag returns 0, as it does in other places in kernel. Signed-off-by: Xin Long Reviewed-by: Simon Horman Reviewed-by: Aaron Conole Acked-by: Florian Westphal Signed-off-by: Jakub Kicinski

net: extract nf_ct_skb_network_trim function to nf_conntrack_ovs

2023-02-11T00:23:03Z

There are almost the same code in ovs_skb_network_trim() and tcf_ct_skb_network_trim(), this patch extracts them into a function nf_ct_skb_network_trim() and moves the function to nf_conntrack_ovs. Signed-off-by: Xin Long Reviewed-by: Simon Horman Reviewed-by: Aaron Conole Acked-by: Florian Westphal Signed-off-by: Jakub Kicinski

netfilter: flowtable: cache info of last offload

2023-02-03T09:31:24Z

Modify flow table offload to cache the last ct info status that was passed to the driver offload callbacks by extending enum nf_flow_flags with new "NF_FLOW_HW_ESTABLISHED" flag. Set the flag if ctinfo was 'established' during last act_ct meta actions fill call. This infrastructure change is necessary to optimize promoting of UDP connections from 'new' to 'established' in following patches in this series. Signed-off-by: Vlad Buslov Signed-off-by: David S. Miller

netfilter: flowtable: allow unidirectional rules

2023-02-03T09:31:24Z

Modify flow table offload to support unidirectional connections by extending enum nf_flow_flags with new "NF_FLOW_HW_BIDIRECTIONAL" flag. Only offload reply direction when the flag is set. This infrastructure change is necessary to support offloading UDP NEW connections in original direction in following patches in series. Signed-off-by: Vlad Buslov Signed-off-by: David S. Miller

netfilter: use skb_ip_totlen and iph_totlen

2023-02-02T04:54:27Z

There are also quite some places in netfilter that may process IPv4 TCP GSO packets, we need to replace them too. In length_mt(), we have to use u_int32_t/int to accept skb_ip_totlen() return value, otherwise it may overflow and mismatch. This change will also help us add selftest for IPv4 BIG TCP in the following patch. Note that we don't need to replace the one in tcpmss_tg4(), as it will return if there is data after tcphdr in tcpmss_mangle_packet(). The same in mangle_contents() in nf_nat_helper.c, it returns false when skb->len + extra > 65535 in enlarge_skb(). Signed-off-by: Xin Long Reviewed-by: Eric Dumazet Signed-off-by: Jakub Kicinski

netfilter: nf_tables: avoid retpoline overhead for some ct expression calls

2023-01-18T12:05:25Z

nft_ct expression cannot be made builtin to nf_tables without also forcing the conntrack itself to be builtin. However, this can be avoided by splitting retrieval of a few selector keys that only need to access the nf_conn structure, i.e. no function calls to nf_conntrack code. Many rulesets start with something like "ct status established,related accept" With this change, this no longer requires an indirect call, which gives about 1.8% more throughput with a simple conntrack-enabled forwarding test (retpoline thunk used). Signed-off-by: Florian Westphal